It is 2.15 on a Tuesday afternoon, with the new term well under way. In a moment I should be hearing the bell heralding the arrival of Period 5 and with it my Year 9 English group. I should be hearing that bell, but I shan’t be, because I’m sitting at home, in a state of suspension.

Friday, January 12 turned out to be my unlucky day: I was attacked - charged, head down with fists swinging - by one of my pupils, a year 9 boy, unhappy that I’d challenged him about yet another missing homework. After his rage was spent and realising that what he’d done was unwise, he seized the initiative and burst into tears, alleging that I’d assaulted him.

The principal, perhaps mindful of the recent, shocking case of Anna Climbie, the eight-year-old who social services failed to spot was being abused to death by her aunt and boyfriend, phoned the authority, social services, and the police. Within an hour and a half I was sent home, pending formal suspension, which was imposed the following Monday. So here I am: no bells, no pupils, but with plenty to think about.

It is a worrying time. I see a sense of theatre in what has happened, as I am asked to hand over all school property, including keys. I am forbidden contact with colleagues and would perhaps have the epaulettes wrenched off my shoulders were my front-line duties of a more military kind.

I feel genuine fear about my future. Supposing the pupils who saw what happened lie or are not asked to give an account; supposing by some stroke of injustice or ill-luck the gross misconduct charge sticks and I am dismissed? The house on which I still have a sizeable mortgage and into which I have put so much work, would have to go. I have no profession or trade other than teaching, and retraining at 42 seems a frightening prospect.

And, although innocent, I feel shame. With an acute sense of irony I recall talking to my form group only a few days before the incident about the evils of gossip: never judge anything or anyone, I told them, unless you’re certain of the facts. Those who did not witness the assault on me, swiftly followed by the accusation that I was the perpetrator, may now have room for doubt about where the truth lies. Fortunately in this traumatic circumstance, I have no wife or children, but my mother, I know, is worried, and I worry myself about its effects upon her health. I alternate between misery, anger, anxiety and restlessness.

So how could it have happened? Oddly, though perhaps there is a connection, it has come at a time when, after 17 years of teaching, I am clearer in my mind about the nature of the problem than I have ever been. Unfortunately, I am equally clear that its solution is further away than ever. The doctor, with whom I registered my injuries on the advice of my union, told me, “The pendulum has swung too far back.” I agree with him; in a way he has the answer, even though he has no experience of secondary school life.

It is true that many headteachers tolerate misbehaviour. My own principal will not allow the terms “bad behaviour” or “misbehaviour”, insisting instead on “challenging” to describe pupils’ disruptiveness. Sanctions must always seek to “reconcile” teacher and pupil, or attempt to show the pupil how he or she has offended, even where this has been tried and failed many times. Though an experienced head of department, with no pretensions to further advancement, I dare not use the word “punishment” in my principal’s presence. Such a concept for her must always be associated with the excesses of the past, when the pendulum of which the doctor spoke was at the opposite end of its arc.

I am not a strict teacher. As a child, I knew which teachers were strict, which of them one was ill-advised to approach, let alone cross. I am uncomfortable with those who advocate a return to those “good old days”. I accept individual rights and the efficacy of child-centred approaches; I allow that our understanding of and response to children’s behaviour, good or bad, should at least be informed by a sense of what is happening to them as people. But there are limits. The laissez-faire pattern which dominates schools throughout much of the state sector militates against learning, both academic and social. I believe it is uncertainty about values that is decisive here.

As a secondary school pupil from the late sixties to the mid-seventies, I was no angel, though there were others much worse. Bad behaviour happened and sometimes it was ineffectively handled; some teachers were too young, or too old, were supply teachers or inexperienced students, or just weren’t very good. But I think that in all instances of misbehaviour there was a clear understanding that someone had done something wrong.

Today, we live in a society where concepts of right and wrong are fragile and if that sounds like the observation of a dyed-in-the-wool traditionalist, a cynic near the end of his career perhaps, I have to say that I am a Guardian reader who has (I hope) 20 years left of his teaching life.

The truth is that teachers are no different from the rest of a society confused by moral relativism and with a complex about words such as “values” when used in any other than an entirely descriptive sense. We work in institutions where it is taboo to discuss such issues in general, and our expectations of pupil behaviour in particular, because pragmatism and self-preservation dictate otherwise. We are never able to acknowledge our uncertainties, much less consider the implications they have for our “front line” role.

Many teachers are profoundly ambiguous about their right to impose their will and their values on young people. Why should the boy who attacked me have to do homework? Are the values of respect for others and honesty which are supposed to underpin my school’s code of conduct, but which the boy so blatantly rejected, really any better than his alternative values or than no values at all? And what of those tiny contentions that consume so much of our daily dealings with pupils? Chewing gum, uniform, foul language? Are we sure we have right on our side? But while doubt about the appropriateness of values persists in the teacher’s mind as well as in the collective social conscience, we must and do continue to pretend that we are all in agreement. Don’t mention the moral vacuum, we tell ourselves, make do and mend; after all, there is always the safe ground of choice, pluralism and individual liberty isn’t there?

Products themselves of a school culture in the nineties where moral uncertainty was already established, and trained on teaching courses which barely allowed a morning for a consideration of educational philosophy, new teachers emerge more reticent than ever as arbiters of right and wrong. Moreover, they emerge into schools where relativism seems to be the official norm and headteachers have a firm grip on staff even though their control of pupils is less impressive. Teachers, especially young ones who still have something to gain from the system of patronage and preferment at the centre of which sits the head, know that to raise their uncertainties is to show weakness or dissent, neither of which is a recommendation for career advancement.

Most damning heresy of all, they must renounce intellectualism: one gets nowhere in teaching by thinking, as all recent reforms to education courses insist; even brief flirtations with social theory during a management meeting are met with embarrassed silence. The pretence of purposefulness continues and the complex-free countenance of the teaching profession seems to remain undisturbed. Meanwhile, pupil behaviour gets worse.

Some good things have come from my experience. A post-traumatic calm sometimes settles over me, one from which I can make sense of what is happening in our schools even though I am powerless to do much about it. More importantly, colleagues have found ways, despite the injunction on contact, to show their concern and their support. an early call reassured me, “A lot of people are thinking, ‘There, but for the grace of GodI’ ” Now I await a call from the police and ponder my future. Perhaps the pendulum will, as pendulums do, move again and sit sensibly for a while at the bottom of its swing. In the meantime, it being a quarter to six, I’d better get home and do some marking. What am I saying? I’m already home.

Mark Harris writes under a pseudonym